Fibroin spinning solutions



' Patented Feb. 7, 1939.

PATENT OFFICE 2,145,856 I rumour ammo sow'noNs Rudolph S. Bley, Milllgan Oollege, Tenth, assignor to North American Rayon Corporation, New York, N. Y., a corporation of Delaware No Dra This is a division of my application Ser, No. 59,912, filed January 20, 1936.

The present invention relates to a process of manufacturing solutions of proteins, such as 5 fibroin, casein, gelatin, wool and alginic acid,

from which the proteins may be precipitated by suitable reagents. 1

, One object of this invention is to prepare a spinning solution containing a protein selected 1 from the group consisting of fibroin, casein, gelatin, wool and alginic acid from which artificial products, such as filaments, yarns, ribbons, films, etc., may be formed.

Another object of my invention has to do with 15 the preparation of a spinning solution by dissolvlng fibroin in a quaternary benzyl substituted ammonium base. 1

A'third object of my invention relates to the manuiacture of fibroin spinning solutions by disn solving a fibroin, such as natural silk, in a quanternary benzyl substituted ammonium hydroxide.

A fourth object of this invention has to doa molecule, this degradation resulting in a decrease in viscosity of such fibroin solutions. In accordance with the presentinvention this degradation oi" the fibroin molecule is substantially counteracted by dissolving naturalsilk in" solutions of a) uaternary'benzyl substituted ammonium bases. 1 have found by experimentation that fibroin may be rapidly and completely dissolved inhighmolecular organic ammonium'bases having the general structure v 45' cancel a.

" i: H Ri' in which 31.1%: and Rs represent alkyi, aryl 0 and/or aralkyl groups'or' sllbstltuted derivatives thereof. -In addition, I-have found that benzyl substituted quaternary ammonium hydroxides are especially suitable for dissolving fibroin, wool,

etc.,.to form spinning solutions. Although, I have found that trimethyl-benzyl-ammonium hydroxwing. Original application I 20, 1936, Serial No. 59,912. Divided and this application April 21, 1938, Serial No. 203,443

- isjomm (01. 106-40) REIISSUED MAY. 2 1 1940 ide is'an excellent solvent for fibroimwool, etc., other quaternary benzyl-ammonium hydroxides may be used for this purpose, such as triethylbenzyl-ammonium hydroxide, dimethyl-phenylammonium hydroxide, diethyl phenyl-ammo- 5 nium hydroxide, dlbutyl-phenyl-ammonium'hydroxide, dimethyl-toIybammOnium-hydrOxide, dimethyl-amyl-benzyl-ammonium hydroxide, di-

-methyl-dibenzylammonium hydroxide, benzyl pyridonium hydroxide, dibutyl-dibenzyl-ammonlum hydroxide, .tolyl-pyridonium hydroxide. etc. In other words, I may use any water-soluble, highmolecular quaternary ammoniumhydroxidewhich has a strong basic reaction and which is ableto dissolve fibroin, wool, cellulose, etc. Benzyl substituted ammonium hydroxides are able to dissolve such substances in relatively short periods of time to form clear, filtrable solutions. The fibroin can be precipitated from such solutions by diluting them with water or by causing the ammonium base to react with acids, acid salts and the like. However, it is to be noted that aqueous solutions of benzyl substituted ammonium hydroxides should be preferably of about to' 50% strength, i. e., about 2 normal. It is also preferable to dissolve 25 fibroin in quaternary ammonium bases at an elevated temperature for the formation of clear, filtrable solutions. However, care must be exercised to avoid decomposition by the solvent by raising the temperature too high. Although it has been found that such fibroin'solutions keep well on standing at ordinary room temperature. the degradation of fibroin may be practically overcome by storing said solutions at a low temperature. The solutions may be dlluted to some 5 extent with water without causing precipitation of fibroin provided suitable emulsifying agents, such as trimethyl-benzyl-ammonium oleate, al-

"kali metal salts oi'fatty acids, etc., are added thereto in suitable proportions.

Any known type of delustering agent which is stable in quaternary ammonium bases, such as oils, pigments, dyestuffs, etc., may be dispersed. by suitable 'means in these fibroln solutions for the production ofsoft-lustre or colored products 5 v therefrom.

Instead of using a fibroin solution per se for the production-oi filaments, yarns, films, etc.,-

I may form mixed spinning solutions containing;

for example, fibroin and cellulose, since both sub- '50 stances may be dissolved in quaternary ammo nium hydroxides. this purpose, I may dissolve for example natural silk and cellulose or a cellulose derivative, such as cellulose esters and ethers in a concentrated,; -aqueous solution of a as benzyl substituted ammonium hydroxide such as trimethyl-benzyl ammonium hydroxide, etc. The fibroin-cellulose' or :fibroin cellulose derivative solution may be subsequently spun into water, dilute acids or salt solutions to form filaments, yarns, ribbons or films. Solutions may also be spun containing fibroin, cellulose and a rubber latex; The solutions set forth above, may be ammonium bases may be recovered from the setand sodium sulphate. .35

ting baths by suitable ,means and re-employed for the dissolution of fibroin, cellulose, wool, etc., to render the process more economical.

Example 1 Natural silk, i. e., fibroin, is dissolved at a moderate temperature in a 25 to 50% solution of trimethyl-benzyl ammonium hydroxide until a solution of sufficient viscosity is obtained. The spinning'solution, thus prepared, is spun with the assistance of spinncrettes into an acid setting bath containing for example dilute sulphuric acid The threads are collected on spools or in pots, washed and dried. Wool, gelatine, alginic acid or casein may be dissolved .in similar manner to form solutions which are spun like'silk fibroin.

Example 2 Natural silk and cellulose are dissolved together in a quaternary ammonium hydroxide, preferably trimethyl-benzyl ammoniumhydroxide, and spun as set forth in Example 1. Instead of cellulose or regenerated cellulose, a cellulose derivative,

i. e., esters and ethers, may be'dissolved together with fibroin. Instead of forming silk fibroin solutions, I may dissolve wool, gelatin, alginic acid or casein in a quaternary ammoniumbase, preferably a benzyl substituted ammonium hydroxide, to form spinning solutions which may contain in addition cellulose, regenerated cellulose, or cellulose derivatives.

Example 3 Fibroin, wool, gelatin, alginic acid or casein solutions with or without cellulose additions are diluted with water after the addition o a suitable emulsifying agent, such as trimethyl-benzyl oleate to such extent that the solid phase is not precipitated, spun and after-treated in accordance with the methods set forth above.

Instead of feeding the spinning solutions, set

forth above, singly to the spinning nozzles, I may extrude-for examplea fibroin solution together with a cellulose solution from 'a single or a 'plurality of spinnerettes and obtain composite products consisting of natural silk and cellulose filaments, etc. In ,this manner, I may also produce mixed products consisting of natural silk, wool,

and cellulose, etc. FurthermorefI may admix pigments or other solid and liquid delusterants withmy spinning solutions for the production of yarns composed of differently colored products, etc. In other words, according to the present invention, any method known'in the rayon art may be used to modify the physical properties of products manufactured from my novel spinning solutions. I wish to emphasize that the substances, set forth above, may be truly dissolvedinthe quaternary ammonium hydroxides or merely finely dispersed therein. Instead of using phenyl substituted ammonium base's I may employ tolyl substituted ammonium bases as set forth in my co-pending application Ser. No. 203,444, filed April 21, 1938.

Modifications of myinvention will readily be recognized by those skilled in the art, and I desire to include all such modifications coming within the scope of the appended claims.

I claim:

1. A spinning solution for the manufacture of artificial products comprising a protein selected from the group consisting of silk fibroin, wool, gelatin, alginic acid and casein finely dispersed in a quaternary phenyl substituted ammonium base having the structure in which R1, R2, and R3 represent a radical selected from the group consisting of alkyl radicals, aryl radicals, aralkyl radicals, substituted alkyl radicals, substituted aryl radicals and substituted aralkyl radicals, said solution having the property of substantially retaining its viscosity on standing for relatively long periods of time at a temperature not exceeding ordinary room temperatures.

2. A spinning solution for the manufacture of artificial products comprising a silk fibroin finely dispersed in a quaternary phenyl substituted ammonium base having the structure in which R1, R2, and R3 represent a radical selected from the group consisting of alkyl radicals,

aryl radicals, aralkyl radicals, substituted alkyl radicals, substituted aryl radicals and substituted aralkyl radicals, said solution having the property of substantially retaining its viscosity on standing for relatively long periods of time'at a temperature not exceeding'ordinary room temperatures.

4. A spinning solution for the manufacture of artificial products comprising an .alginic acid finely dispersed in a quaternary phenyl substituted ammonium base having the structure aryl radicals,

HO RI "in which R1, R2, and R: represent a radical selected from the group consisting of alkyl radicals, aralkyl radicals, substituted alkyl radicals, substituted aryl radicals and substituted aralkyl radicals, said solution having the property of substantially retaining its viscosity on,

standing for relatively long periods of time at atemperature not exceeding ordinary room temperatures.

5. A spinning solution for the manufacture of artificial products comprising a protein selected from the group consisting of silk fibroin, wool,

gelatin, alginic acid and casein finely dispersedin a. dibutyl-phenyl-ammonium hydroxide, said solution having the property of substantially retaining its viscosity on standing for relatively long periodsof time at a temperature not exceeding ordinary room temperatures.

6. A spinning solution for the manufacture of artificial products comprising a silk fibroin finely dispersed in a dibutyl-phenyl-ammonium hydroxide, said solution having the property of substantially retaining its viscosity on standing for relatively long periods of time at a temperature not exceeding ordinary room temperatures.

'7. A spinning solution for the manufacture of artificial products comprising a casein finely dispersed in a dibutyl-phenyl-ammonium hydroxide, said solution having the property of substantially retaining its viscosity on standing for relatively long periods of time at .a temperature not exceeding ordinary room temperatures.

8. A spinning solution for the manufacture of artificial products comprising an alginic acid finely dispersed in a dibutyl-phenyl-ammonium hydroxide, said solution having the property of substantially retaining its viscosity on standing for relatively long periods of time at a temperature' not exceeding ordinary room temperatures.

9. A spinning solution for the manufacture of artificial products comprising a protein selected from the group consisting of silk fibroin,'wool, gelatin, alginic acid and casein finely dispersed in a quaternary phenyl substituted ammonium base having the structure C|Hs\" NgR: 110 R:

in which R1, Ra,.and Ra represent a radical selected from the group consisting of allryl radicals,

aryl radicals, aralkyl radicals, substituted allryl radicals, substitutedaryl radicals and substituted '-aralkyl radicals together with a cellulodc substance selected irom' the group consisting of cellulose, cellulose esters and ethers, said solution having the property of substantially retaining its viscosity on standing for relatively long periods of time at a temperature not exceeding ordinary room temperatures.

10. A spinning solution for the manufacture of artificial products comprising a silk fibroin finely dispersed in a quaternary phenyl substituted ammonium base having the structure 00H R1 NRz no R; in which R1, R and R: represent a radical select- .ing room temperatures.

N l'h 110 Rt in which R1, R2, and Rs represent a radical selected from the group consisting of alkyl radicals,

aryl radicals, arallryl radicals, substituted alkyl radicals, substituted aryl radicals and substituted aralkyl radicals together with a cellulosic substance selected from the group consisting of cellulose, cellulose esters and cellulose ethers, said solution having the property of substantially retaining its viscosity on standing for relatively long periods of time at a temperature not exceed- 12. A spinning solution for the manufacture of artificial products comprising alginic acid finely dispersed in a quaternary phenyl substituted ammonium base having the structure in which R1, R2, and R3 represent a radical selected from the group consisting of alkyl radicals,

I aryl radicals, aralkyl radicals, substituted alkyl radicals, substituted aryl radicals and substituted aralkyl radicals together with a cellulosic substance selected from the group consisting of cellulose, cellulose esters and cellulose ethers, said solution having the property of substantially retaining its viscosity on standing for relatively long .7

periods of time at a temperature not exceeding normal room temperatures.

13. A spinning solution for the manufacture of artificlai products comprising a protein, selected from the group consisting of silk fibroin, wool, gelatin, alginic acid and casein finely dispersed in a dibutyl-phenyl-ammonium hydroxide together with a cellulosic substance selected from the group consisting of cellulose, cellulose esters and cellulose. ethers, said solution having the property of substantially retaining its viscosity on standing for relatively long periods of time at a temperature not exceeding ordinary, room temperatures.

- 14. A spinning solution for the manufacture of artificial products comprising a silk fibroin finely'dispersed in a dibutyl-phenyl-ammonium hydroxide together with a cellulosic substance selected from the group consisting of cellulose,

cellulose esters and cellulose ethers, said soluv tion having the property of substantially retaining its viscosity on standing for relatively long periods of time at a temperature not exceeding ordinary room temperatures.

I 15. A spinning solutionfor the manufacture of artificial products comprising a casein finely dispersed in a dibutyl-phenyl-ammonium hydroxide together with a cellulosic substance selected from the group consisting of cellulose, cellulose esters and cellulose ethers, said solution having the property of substantially retaining its viscosity on standing for relatively long periods of time at a temperature not exceeding ordinary room temperatures.

16. A spinning solution for the manufacture of artificial products comprising an alginic acid finely dispersed in a dibutyl-phenyl-ammonium hydroxide together with a cellulosic substance selected from the group consisting of cellulose, cellulose esters and cellulose ethers, said solution having the property of substantially retaining its viscosity on standing for relatively long periods of time at a temperature not exceeding ordinary room temperatures.

RUDOLPH S. BLEY. 

